function [] = calcEstimations()
    %% initialization:
    iNElem = 8; % number of elements in the array ...
    iSize = ceil(iNElem/2);

    dRho = 0.0; % traffic intensity value ...
    a_W = zeros(1, iSize);
    a_Wt = zeros(1, iSize); % theoretical queue length (L) ...
    a_rho = zeros(1, iSize);
    
    a_means = zeros(1, iNElem);
    for i=1:2:length(a_means)
        a_means(i) = 1.0; % mean of arrival time (lambda) ...
        a_means(i+1) = (i+1)/(iNElem+2); % mean of service time (mu) ...
    end
        
    meanVals = zeros(1, 2);
    
    %% simulation:
    % calculate the estimations of the temporal mean of the clients in a system ...
    iCount = 1;
    for i=1:2:iNElem
        fprintf('\nit_nr: %d\n\n', iCount);
        
        meanVals(1) = a_means(i);
        meanVals(2) = a_means(i+1);
        [dR, dRelError, mean_W] = mm1W(meanVals);
        dRho = dR;
        
        % add the empirc mean value to the array ...
        a_W(iCount) = mean_W;
        a_rho(iCount) = dRho;
        
        % calculate the theoretic mean time of arrivals ...
        dW = 1.0/((1/meanVals(2)) - (1/meanVals(1)));
        a_Wt(iCount) = dW;
 
        iCount = iCount + 1;
    end
    
    % verify the length of the arrays with the count number ...
    if(length(a_W) > iCount)
        % cut all arrays at the count position ...
        a_W = a_W(1:iCount);
        a_Wt = a_Wt(1:iCount);
        a_rho = a_rho(1:iCount);
    end
    
    % plot the theoretical and the empiric vallue of L (length of the queue + 1) ... 
    cGrey = [0.4, 0.4, 0.4];
    cDarkGrey = [0.2, 0.2, 0.2];
    iStdSize = 12;
    %iTitSize = 14;

    figure(2);
    clf;

    hold on;
    g = plot(a_rho, a_W, '-');
    f = plot(a_rho, a_Wt, '--');
    
    set(f, 'LineWidth', 1, 'Color', cDarkGrey);
    set(g, 'LineWidth', 1, 'Color', cGrey);
    
    l = legend( [f g], '\it valor empirico', '\it valor teorico' );
    set( l, 'Interpreter', 'tex', 'Location', 'NorthWest', ...
            'FontName', 'Times', 'FontSize', 9 );

    xlbl = xlabel( 'intensidad de trafico \rho' );
    ylbl = ylabel( 'tiempo medio en el sistema por cliente \it{W}' );
    set(xlbl, 'Interpreter', 'tex', 'FontName', 'Times', 'FontSize', iStdSize);
    set(ylbl, 'Interpreter', 'tex', 'FontName', 'Times', 'FontSize', iStdSize);
    %title(' ', 'FontName', 'Times', 'FontSize', iTitSize);
    
    axis normal;    
    grid on;
    hold off;

    % print the theoretic and the empiric values in one list ...
    fprintf('\n\nvalues:\n');
    fprintf('rho,\t\ttheoretic,\tempiric\n');
    for i=1:length(a_Wt)
        fprintf('%f,\t%f,\t%f\n', a_rho(i), a_Wt(i), a_W(i));
    end
end

%% result (output):
%
